Stair construction



H. L. FELDBLET AND IR. ODONNELL.' v

. STIR CONSTRUCTION APPLICATION FILED IEB. I. I92I. REIIEwED IuLY I7, 1922.

2,427,276, Patented Aug. 29, 1922.

K SHEET SHEET I.

s i II- H. L. FELDBLET AND J. R. ODONNELL.

STAIR CONSTRUCTION APPLICATION FILED H:B.I,192| RENEWED JULY 17, 1922. '1,427,275 1PatemaAug.29,1922.

F. 3 SHEETS-SHEET 2.

l` H. L. FELDBLET ANDJ. R. ODONNELL;

STAIR CONSTRUCTION.

- 4APPLICATION EILED FEB. l. 1921. RENEwED 1uLY17.1922. 1,427.276.

@HGH .Q @H E @n www keuren stares PATENT orifice.;

HERMAN L. FELDBLETANKD JOHN ROBERT ODONNELL, UF NEW YORK,y 'N. Y.

inerme.

Specification of Letters Patent. Patented 'lugi 29,

Application led February 1, l921,`Seria1\No. 441,646. Renewed July 17, i922. SerialiNa 575,758.

kof which the following is a speciiication.

kThe invention relates to a stair construction employing both Structural steel and structural reinforced concrete elements as carrying members, all so combined as to producek a more economical and otherwise more satisfactory reproof stair than otherexisting types of all steel or composite structures. y

Plain reinforced concrete stairs are made of ordinary concrete ingredientsreinforced withv steel bars and supported on a temporary wood form-work until the concrete has attained sutlicent strength to supportfitself across the span, at which time the wood forms are removed. This construction is costly, because of the nature of the forms necessary to support ythe wet concrete yand because of the heavy concrete slab and reinforcing `required under the steps in order to supply the necessary strength.

The present invention recognizes the possibility of using a combination of structural or pressed steel strings with inwardly projecting flanges, in conjunction with continuous monolithic reinforced concrete steps Y moldedat opposite sides into the strings. In this way the steps are supported in part by the flanges and in part by the continuous section ofreinforced concrete beneath the treads. This continuous section of concrete connecting` the steps together is `materially thinner than the section required beneath the risers intheplain concrete construction, and the internal reinforcing is also much lighter, so that the new construction is considerably less massive and less expensive.

The invention is further based 'upon the recognition that by using these steel strings and designing the stair in the fashion described above, there is not only provided an economical design as far as the elements .of the structure are concerned, but it also becomes possible to provide an economical vmeans of attaching and supporting a iiexible system of forinwork, with which it is readily possible to handle different widths of stairs and 'different types of risers by mal;-

iiig simple adjustments in` stock equipment;

The invention thus s involves a combined structural steel and reinforced poured-in place stair construction, in rwhich the' steel strings, and preferably constructed substan-y tially as hereinafter described.

ln the accompanyingdrawings, forming a part hereof:

Fig. l is a vertical longitudinal section through a portion of the form-work; p

l Fig. 2 is a top plan .projection of aportion of one of the strings, indicating also the end of one `of the riser-forms;

Fig. 3 is a plan view ofthe form-work ywith the lower portion vcut off in an `inclined Plane;

Fig. 4C is a section on the line 4;-4 of Fig. l; y

rFig` 5 is a section on the line 5--5 `of Fig. l; s

Fig. G is a perspective view of onek endof one ofthe riserfforms; f

Fig, 7 is a front elevationof a riser-form; Fig. Sis'ay vertical longitudinal section through a portion of the completed stair: andk Fig. 9 is a vertical transverse section on the line 9 9 of FigQS. y

The inclined strings 1 may be standard channel iron, pressed steel sections, or of a built-up section. They are disposed with their lower and upper ialnges 2, `3 project ing inward. Between these strings are supported riser-forms 4, and an inclined floorform 5 is secured beneath them.

Movable triangular blocks Gare secured at the inner sides ofthe strings beneath-the top kflanges 3, being so' designedand positioned as to lie in the angles between the treadsl and risers of the stairs tobe constructed. As shown more' particularly in Figs. l, 4l and 5 the blocks areformedto fit against the web and upper flange offeach of the strings, and to be spaced at some -distance yfrom the lower flange.` f

s An angular piece 7 has its vertical portion secured by fastenings y8 to the inner face of each ofthe blocks 6 with its horizontal or laterally-extending portion 9 disposed at a distance above the block and kprojecting outwardly so as to extend over the top of the ange 3. A set-screw 10, threaded through an opening in the said portion 9 to bear against the top of the liange, completes a clamp whereby each movable block can be secured at any point along the string.

The vertical rear ends of the lilocl 6 afford abutments for positioning and sustaining the riser-forms e against the` forward pressure of the concrete. For this purpose the rear inner corners of the blocks are preferabl f notched or recessed as indicated at 11 in l* ig. 2, the depth of the recesses be* ing equal to the width of the end portions of the riser-storms, so that the backs of the latter are ilush with the ends of the blocks. The end faces 12 f the riser-forms are advantageously beveled to lit correspondingly beveled opposed faces of the notches in the blocks. The riser-forms are supported against dropping by top end projections 13, which rest upon the tops of the strings. These pieces are preferably angle members, comprising vertical and horizontal flanges the edges of which are beveled to iit the sloping tops of the strings.

Each of the riSer-fOrms .is constructed of relatively movable sections, so that they can be set for various width of stair, and is also flexible as to height. In the preferred embodiment, the form comprises a single panel section 1li, which forms the recessedpanel 1112* in the front of the riser of the concrete stair. In'addition to this panel section, each riser-form includes two front sections 15, which are movable longitudinally in opposite directions upon the panel section. The front sections extend beyond the ends ofthe panel section and also extend above it. Bolts 16 projecting forward from the panel section, through horizontal or longitudinal slots 17 in the front sections. to-

gether with nuts 18 on the front ends of the bolts, afford means for holding the sections together while permitting thel relative movement. A vertical wedge 19. interposed between the proximate ends of the movable front sections, constitutes an expanding device whereby the front sections can be maintained at various degrees of horizontal extension. The wedge may be retained in place by undercutting the inner ends of the sections 15 and preferably also by means of a `keeper'2i extending across the front of the wedge and suoported byy two of the bolts 16 at opposite sides.

Verticalextension is secured by theV provision of means whereby the projecting end pieces `13 can be locked at various heights on the sections 15, thus raising and lowering the bottoms of the riser-forms andV permitting strips 20, see Fig. 1, to be added atA the top.` For this purpose the body portions 21 of the vertical portions of the pieces 13 which overl'ie the front faces of.. the see tions 15 are shown provided with vertical slots 22 to cooperate with bolts and nuts 23 on the said sections. By utilizing a suitable number ofthe supplementary sections 2l) the riser-forms can be built up to the desired height. K

rEhe riser-forms may be secured to the blocks 6 against rearward displacement by' means of eyes 25 on the front sides of the end portionsof the sections 15, registering vertically with eyes 26 on the lower portions of the blocks to receive pins 27 which are dropped through the registering eyes.

rl`he floor-form l may be of wood or metal, and is made in standard sections, so that variable Widths can be obtained. The sections of which it is composed are supported on cross-pieces 27, the ends of which extend beyond the sides of the form. rlhe said ends are longitudinally slotted, as indicated at 28, to cooperate with hanger rods or bolts 29, which extend downward from the upper portions of the strings through the slots 28, beneath which they are provided with heads or nuts 30. Cross-brackets 31 are fixed to the top portions 9 of the clamps of certain of the blocks 6. The opposite ends of these cross-brackets project respectively beyond the outer sides of the strings and the inner sides of the blocks, and are formed with holt-holes 32 adapted to receive the upper ends of the hanger rods 29. By tightening the nuts 30, the cross-pieces 27 are clamped upward against the strings or against intervening spacing wedges 34. The

blocks 6 thus not only aiford means for positervals. It is preferable to locate the hangers 29 at the outer sides of the strangs, as illustrated, but where conditions will not permit of this they may be engaged with the bolt-holes in the bracket pieces 31 at the inner sides, the hangers then passing through the floor.

lilith the form-work set up, reinforcing rods are arranged longitudinally above the floor and below the riser-forms, and other reinforcements 36 are arranged transversely.r r)The concrete isvthen poured, `and when in the proper condition troweled off at the treads. VlThen the concrete is sufliciently set, the bloclr6, the riser-forms 21- and the .floor-form 5, with itstransverse supports 27, are all removed, leaving the channel strings 1 and the monolithic reinforced concrete steps 36 cast therein and supported upon the bottom flanges, asv illustrated in Figs. 8 and 9. The removal of the blocks 6 leaves recesses beneath the top ianges 3 in the angles between the treadsy 3'? and risers'58,.wheh recesses are preferably filled by inserting small eonerete blorlis lV e arev aware that ithas been proposed .to malte -a sta-irof channel strings and preeast cellular Concrete step blocks. ,rl`his, however, is anassembled Constructiony and laolrs the characteristics of our integral monolithic ,construction east into the strings 1and having a continuous ybottom section. .f

form-work and eventually entering `into v.the

permanent construction,movable bloeksr seenred at the inner sidesofsaidistringsa and riser-forms extending between the strings and iiiidingforward yabutment supportl .against said' bloelisi j 3. In concrete stair Construction, the eombination of strings having inwardly disposed flanges, said strings constituting part of the form-work and eventually entering into `the permanent eonstruetiom movable blocks seeured at the inner sides of said strings, riserlorms extending between the strings and finding forward abutment support against said blocks, a lioor-form and means suspending said floor-form from said blocks.

l. ln eonerete stair construction, the eonibination of strings having inwardly disposed flanges7 said strings constituting pait of the form-work and eventually entering into the permanent construction, movable bloels at 'the inner sides of the strings having clamps extending over the top flanges of the strings, riser-forms having forward abutment support at their ends against said blocks, a floor-form, and hangers extending downward from said clamps to said floor-form.

ln concrete stair construction7 the combination of strings having inwardly disposed flanges, said strings constituting part of the form work and eventually entering into the permanent construction` and means for sustaining forms in position on the strings eomprising movableblocks at the inner sides of said. stringsbeneath the top flanges thereof and having parts extending over said flanges, and serews insaid parts for Clamping the blocks to the flanges.

6. .ln concrete stair eonstruetion, the combination of strings having inwardly disposed flanges, said strings constituting part of the form-work and eventually entering into the permanent construction, and means for sustaining forms in position on the strings comprising movable triangular blocks adapted lto; lie at treadfan :for securing them to the strings.

riserv'fangles, and having Clamps Tin eonerete stair eonstruetion, the oomfbination of strings havinginwardly disposedy flanges, said strings constituting part of the lorm-worlrl and 'eventually entering into `the permanentconstruction,y and means for susitaining forms in position on thestrings oomprisiiig movable. blocks` at `the innersides andjbeneath ythe. topA .flanges of the strings, yandy having :Clamps extending over said :flanges 1 f f 'e "53. ln concrete stair Construction, the combination of strings havinginwardly disposed y vflanges, said strings constituting part of the n liornrworl:and eventually7 yentering into the :permanent construction," movable` blocks se- Eeured the inner sides and beneath the top flanges oi thestrings, and extensible riserf yforms forwardly supported atv their ends 1 9." In eoneretestair eonstruetion 'the oom- .bination ofwstrings havinginwardly disposed f said strings constituting part of the lormrworkvand eventually entering into the K' permanent construction,v extensible riserforms supported by and between said strings floor-form having supporting erosspieees slotted at their ends, and fastenings between the strings and the cross-pieces passing through said. slots.

10. ln concrete stair construction, the oombination of strings having inwardly disposed flanges, said strings constituting part of the form-work and eventually entering into the permanent construction, movable blocks se# cured` at the inner sides of said strings, and riser-forms -forwardly abutting at their ends against said blocks and having top end pieces resting on the strings.

ll. ln eonerete stair eonstruetion, the eombination of strings having inwardly disposed flanges, said strings constituting part of the form-work and. eventually entering into the permanent construction, movable blocks seeured at the inner sides of said strings,r risere .inner sides of the strings in the forms forwardly abutting at their ends against said blocks, said forms being coinposed. of relatively movable sections yaffordinglongitudinal adjustment, and top end pieees vertically adjustable on the relatively movable sections to rest on top of the strings.

l2. ln concrete stair Construction, the eom-y bination of strings having inwardly disposed flanges, said strings constituting part of the form-work and eventually entering into the permanent construction, movable blocks vsecured at the inner sides of said stiings,riser forms forwardly abutting at their ends against said blocks, and angle pieces projecting end wisefrom the tops of the riser-forms to rest on the sloping tops of the risers.

i3.. In concrete stair construction, the combination of strings having inwardly disposed flanges, said strings constituting part of the form-work and eventually entering into the permanent construction, and riser-forms supported by and between said strings,

each of said riser-forms comprising a panel section at tlie back and a pair of front sections extending beyond the panel section and movable in opposite directions lengthwise thereon.

14. In concrete stair construction, the combination of strings having inwardly disposed flanges, said strings constituting part of the form-work and eventually entering intothe permanent construction, movable blocks secured at the inner sides of said strings beneath the top flanges so as to occupy the angles between treads and risers, extensible sectional riser-forms extending between the strings in abutment with said blocks, and

f means for supporting floor-forms of variable -width from and beneath the strings.

l5. In concrete stair construction, the combination of strings having inwardly disposed flanges, said strings constituting part of the l ormwvork and eventually entering into the permanent construction, riser-forms extending between the strings, a floor-form, crosspieces beneath the Hoor-form, and fastenings between said cross-pieces and strings.

16. A riser-form for concrete stair construction comprising a panel section at the back, a pair of front sections extending beyond the ends of the panel section and longitudinally movable in oppositey directions thereon, means holding the sections together and permitting suoli movement, and an expanding device between said front sections.

17. A riser-form for concrete stair construction comprising a panel section at the back, a pair of front sections extending beyond the ends of the panel section and longitudinally movable in opposite directions thereon, means holding the sections together and permitting Such movement, an expanding device between said front sections,` pieces on the remote ends of said front sections affording to end projections, and means for looking sai end pieces to the front sections at different heights.

HERMAN L. FELDBLET. JOHN ROBERT ODONNELL. y 

